I like leaving people the option of using the status update feature, but not everybody has that widget in place on their home page and my users are now receiving "reminder' emails asking them to set their status update. How do I turn off these reminders?

Users can disable these reminders themselves in their profile. You can also disable them in the Admin Console. And additionally, you can modify the text of that email so that it doesn't prompt them to update their status. There is actually a lot of flexibility with these digest emails.